Thromboxane A.sub.2 (TxA.sub.2), which is a product of the "arachidonic acid cascade", has been found to be a very potent platelet aggregator and pulmonary and systemic vasoconstrictive agent. TxA.sub.2 is produced by the conversion by thromboxane synthetase of the prostaglandin endoperoxide, and PGH.sub.2, which is a cyclooxygenase metabolite of arachidonic acid. TxA.sub.2 has been suggested as an important mediator of thrombosis, endotoxic shock, pulmonary hypertension and cardiac anaphylaxis. By antagonizing the effects of TxA.sub.2 in the circulatory system the compound of this invention is valuable in the treatment of diseases in which TxA.sub.2 is a factor.
N,N'-Bis[7-(3-chlorobenzeneaminosulfonyl)-1,2,3,4-tetrahydroisoquinolyl]dis ulfonylimide, which is disclosed and claimed in U.S. Pat. No. 4,315,935 as antagonizing the effects of slow reacting substance of anaphylaxis (SRS-A) on bronchial smooth muscle, has been discovered to be an end organ antagonist of TxA.sub.2. Therefore, it would be useful in the treatment of diseases in which TxA.sub.2 is a factor.